JPH0113849B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flexible tube for an endoscope having partially different bendability.

In general, an endoscope used for medical treatment, etc., as shown in FIG. The operating section main body 1 includes an eyepiece section 3, a bending operation knob 4, an insertion port 5 for an affected area treatment instrument such as forceps, an air/water supply button 6, a suction button 7, etc. The light guide cord 8 is connected to a light source device for illumination. The body cavity insertion section 2 includes a bendable long flexible tube 9 connected to the operating section main body 1, and a bendable long flexible tube 9 connected to the operating section main body 1. A curved tube 10 for displacing the distal end component 11 in an arbitrary direction by the operation knob 4, and a curved tube 10 connected to the curved tube 10,
It consists of a distal end component 11 provided with an illumination window, an observation window, a treatment instrument entrance/exit, an air/water supply port (none of which is shown), and the like. The inside of the flexible tube 9 and the curved tube 10 of the body cavity insertion section 2 include light transmission members such as image guide fibers and light guide fibers, treatment instrument insertion tubes, air/water supply tubes, and curved operation wires. Many built-in members, such as operating members (none of which are shown), are inserted through the
Each tip of each of these built-in members is a tip portion forming part 1.
It is fixed within 1.

When performing observation or treatment with an endoscope configured in this way, the flexible tube 9 that constitutes the intrabody cavity insertion section 2 is inserted into the body cavity. In order to facilitate insertion, a certain degree of flexibility is required. However, if the flexible tube 9 has good flexibility over its entire length and is too soft, it will be difficult for the operating unit to control the operation of the endoscope tip component 11 within the body cavity. Become. Therefore, a flexible tube is desired that has different bendability on the operating section side and on the distal end component side.

However, generally, the flexible tube 9 has a spiral tube-like flex (flexible body) 12, as shown in FIG.
It is composed of a tubular blade (wire mesh) 13 fitted around the outer periphery of the flex 12, and an outer skin 14 made of an elastic material such as thermoplastic resin or synthetic rubber and coated on the outer periphery of the blade 13. As shown in FIG. 3, the flex 12 is formed by uniformly spirally winding a band-shaped thin elastic plate.

However, in such a configuration, as is clear from the drawings, the flexibility of the flexible tube 9 is uniform over the entire length, and the above problem cannot be solved.

In order to solve this problem, the following proposals have been made in the past.

That is, as shown in FIG. 4, the helical winding pitch of the flex element 12a made of a band-shaped elastic thin plate is partially different, so that a tightly wound part 12' with a small pitch and a coarsely wound part 12 with a large pitch are formed. It has been proposed that a flexible tube is formed by forming a flex 12 with ``2'', and using this to configure a flexible tube with partially different bendability in the longitudinal direction. The flexibility of 12' is deteriorated to some extent,
On the other hand, although the flexibility of the coarsely wound portion 12'' can be improved, since the pitch is large in the coarsely wound portion 12'', the winding gap portion 1 of the flex element 12a
As shown in 2b, there is a possibility that a portion that is weak against compression is formed locally and is easily crushed, making it impossible to sufficiently protect the built-in member. In addition, although the coarsely wound portion 12'' with a large pitch has good flexibility, when it is bent, the curved surface is not smooth and has severe irregularities, which may cause damage to the blade 13 and built-in components. It had the disadvantage of being stored away.

In addition, in order to improve the drawbacks of this proposed technology, it is considered to make the width of the flex element 12a made of a strip-shaped thin plate, which is the constituent material of the flex 12, smaller and further reduce the winding pitch to change the pitch. However, even with this method, the number of turns per unit length is too large, so when one end of the flex is rotated, the rotational force is not sufficiently transmitted to the other end, resulting in poor followability. This brings about the drawback.

The present invention has been made in order to improve the drawbacks of the conventionally proposed technology, and is made of a flex element consisting of multiple flex elements wound helically, and in which the flex elements are formed to have partially different bending properties. An object of the present invention is to provide a flexible tube for an endoscope, which is constructed using the above-mentioned flexible tube and has different bendability on the operating section side and on the distal end component side.

Next, the present invention will be explained in detail based on Examples. FIG. 5 shows flexes 15a, 15 used for the flexible tube of the endoscope according to the present invention.
b and 15c are flex elements each made of a band-shaped elastic thin plate, and these three flex elements 15
a, 15b, and 15c are arranged in parallel to form a set of flex elements, and one part of this set of flex elements is tightly wound spirally to form a tightly wound part 15', and the other part is tightly wound in a spiral manner. The multi-wound flex 15 is constructed by winding the flex helically with a certain distance between each element and between each turn to form a coarsely wound portion 15''.

In addition, in FIG. 5, the tightly wound portion 15' is not only between each element, but also between each winding (for example, 15c and 15').
a′) is also shown in which the windings are formed in close contact with each other, but the pitch between these windings may be increased to provide a certain amount of spacing. I showed what was there, but this is also 4
It may be a number of strips or more than one strip.

Flexible tube flex 15 configured in this way
Since the loosely wound portion 15'' is also formed by multiple windings, it is possible to change the bending portion in the longitudinal direction without creating a locally weak portion against compression as in the prior art. In addition, since it has a multi-wound structure, sufficient followability can be obtained, and a flex formed by arbitrarily selecting the number of threads of the flex element constituting the multi-wound flex and the spiral winding pitch can be used. By doing so, flexible tubes with various mechanical properties can be obtained.

FIG. 6 shows a second embodiment of the flexible tube used for the flexible tube, and like the first embodiment, it has three
Using strips of flex elements 16a, 16b, and 16c, these elements are arranged in close contact and in parallel to form a set of flex elements, which are then spirally wound at the same pitch to form a spiral tubular body. In the middle part, for example, the central flex element 16b
The flex 16 is constructed by cutting and dividing into two parts, removing one of them, and removing the other. As a result, the flex 16 is formed with a three-threaded part 16' and a two-threaded part 16'', and by using these to form a flexible tube, it is possible to give partially different bending properties. .

FIG. 7 shows a third embodiment of the flex. Similarly to the second embodiment, three flex elements 17a, 17b, 17c are closely connected in parallel to form a set of flex elements. After winding this spirally with the same pitch, a part of the element is cut and removed at the middle part to form the flex 17. In this embodiment, the material or wall thickness of each flex element is It changes the dimensions of etc. For example, the thickness of the flex element 17b was made thicker than that of the flex elements 17a and 17c, and similarly to the second embodiment, the flex element 17b having the same thickness was cut at the middle part and one of the flex elements was removed. When using Flex 17, the second
The change in flexibility can be made larger than that in the example. Incidentally, if it is desired that the shape and dimensions of each flex element be the same, the same effect can be obtained by forming one of the elements using a material with excellent mechanical properties and high rigidity.

FIG. 8 shows a fourth embodiment of the flex, in which, like the second embodiment, three flex elements 18a, 18b, 18c are closely connected in parallel to form a set of flex elements. After winding spirally with the same pitch, part 1 of the winding part
The flex 18 is constructed by connecting the elements constituting 8' with adhesive, brazing, welding, or the like. Three flex elements 18
a, 18b, and 18c are wound in close contact with each other as a set, but since they have a certain degree of freedom when they are just in close contact with each other, the combined winding parts are joined by welding etc. It is clear that there is a difference in flexibility between the part 18' and the tightly wound part 18'', which is simply tightly wound. Therefore, according to this embodiment, by coating with adhesive, etc. Flexibility can be changed relatively easily.

As explained above in detail based on the examples,
In the present invention, the flex of the flexible tube for an endoscope is constructed using a multi-strand flex element wound spirally, and its bendability is partially different. It is possible to obtain a flexible tube that has different bendability on its sides, is easy to insert into a body cavity, and is easily controllable from the operating section. In addition, since the flex is made of multiple flex elements, there are no localized areas that are vulnerable to compression, and the curved surface can be made smooth, so there is no damage to the blade or built-in components. Effects can be obtained.

[Brief explanation of drawings]

Fig. 1 is a partially omitted external view of a general endoscope, Fig. 2 is a partially cutaway perspective view of a flexible tube of a general endoscope, and Fig. 3 is a partially cutaway view of a general endoscope. FIG. 4 is a plan view of a conventionally proposed flex, and FIGS. 5 to 8 are examples of the flex used in the flexible tube of an endoscope according to the present invention. FIG. In the figure, 1 is the operation unit main body, 2 is the body cavity insertion part, and 3
is an eyepiece, 4 is a bending operation knob, 8 is a light guide cord, 9 is a flexible tube, 10 is a bending tube, 11 is a tip component, 12 is a flex, 13 is a blade,
14 is an outer skin, 12' is a tightly wound part, 12'' is a loosely wound part, 15a, 15b, 15c are flex elements,
15' is the tightly wound part, 15'' is the coarsely wound part, 16' is the 3
16'' is a double-wound portion, 18' is a combined wound portion, and 18'' is a closely wound portion.

Claims (1)

[Scope of Claims] 1. In a flexible tube for an endoscope, which is composed of a helical tube-shaped flex, a net-like blade disposed on the outside of the flex, and an outer skin disposed around the outer periphery of the blade, the flex is arranged in a spiral shape. What is claimed is: 1. A flexible tube for an endoscope, characterized in that the flexible tube is constructed using a multi-thread flex element wound around the tube so that its bendability differs partially. 2. A flexible tube for an endoscope according to claim 1, characterized in that the flex is constructed by winding multiple flex elements in a spiral shape with partially changing pitches. 3. A flexible tube for an endoscope according to claim 1, wherein the flex is constructed by partially varying the number of multiple flex elements wound spirally. 4. An endoscope according to claim 3, characterized in that the flex is constructed by making the material or shape of some of the flex elements different from each other in multiple flex elements wound in a spiral shape. Flexible tube. 5. Claim 1, characterized in that the flex is constructed by partially fixing each element of a multi-strand flex element wound in a spiral shape by adhesive, brazing, welding, etc. The flexible tube of the endoscope described in Section 2.